I predict Over The "Period" will take longer to pass on Encore Extra Stage than Valkyrie dimension. Valkyrie took 115 days, from 2010-7-14 to 2010-11-06. OT"P" was revealed on 2015-3-26. 115 days after that will be 2015-7-19.

Welp, looks like that prediction came true, for at least (at the time it was written, OT"P" had not been unlocked yet).